May-2024

Integrating CCS and synthetic fuels production in a refinery

A suggested configuration for a hybrid refinery as a fuels production centre uses proven and existing technologies, operating in tandem with existing units.

Juan Carlos Latasa López
IDOM Consulting

Article Summary

This article analyses suggested configurations for ‘fuels production centres’ as the new paradigm for existing refineries, including yields and techno-economic figures. The modern, industrialised world needs a constant supply of energy to sustain the population, its technology and knowledge. This energy encompasses the fuels required for industry, transportation and heating, as well as electricity for lighting, heating and cooling, and general power needs.

The last century has witnessed unprecedented developments in society and technology. However, this progress has come at a high cost due to the negative impacts of our primary energy consumption in terms of atmospheric pollution and contamination of water and land, as well as our impact on biodiversity.

However, the coexistence of human development with nature is possible through an organised and smart approach: the energy transition. These are not just words but a concept of responsibility supported by science that clearly shows we must act now. We need to act decisively and honestly with realistic implementation of technology for improvement without disruption or denial.

The following concepts need to be developed together to optimise a balance among them:
•    Reliable technology
•    Effective reduction of carbon footprint
•    Attractive returns for funds and investors.

Carbon footprint in Europe and worldwide
A question that arises in relation to the growing demand for energy and fuels and the consequent increase in carbon footprint is: Do we want a future for ourselves and the planet? Of course, the answer is always a resounding ‘yes’, but how can we chart a feasible pathway towards a better future while also meeting the energy needs of the world?

The answer does not come from technology billionaires or any magic recipe; it can only be provided by an effective combination of technology, finance, environmental regulations, and supportive taxation policies.

In line with population growth and industrialisation, the global carbon footprint has been steadily increasing for centuries, but with a major increase over the last decades. Several countries and regions are responsible for most of the global emissions (see Figure 1):
- Emissions continue growing. Even in 2022, global greenhouse gas (GHG) emissions primarily consisted of CO2 resulting from the combustion of fossil fuels (71.6%), with CH4 contributing 21% to the total.
- Former low social development countries continue to increase their emissions as they strive for economic growth.
- China, the US, India, the EU27, Russia, and Brazil were the six largest GHG emitters in 2022. Together, they accounted for 50.1% of the global population, 61.2% of the global Gross Domestic Product (GDP), 63.4% of global fossil fuel consumption, and 61.6% of global GHG emissions.
- Only three countries account for 53% of total CO2 emissions and have not pledged to the UNFCC agreements.
- As part of the COP process, countries have submitted Nationally Determined Contributions (NDC), which are commitments to reduce emissions. The IEA in its scenarios has estimated the impact of these current commitments and compared this with a scenario based on what is needed to reach net zero by 2050 (IEA, 2021). In summary, the sum of the NDCs is insufficient to limit emissions and meet the agreed target, meaning all countries must increase their ambition.
- In the IEA Net Zero Emissions scenario, all countries pledge to achieve net zero, and global warming will reach a maximum of +2ºC by 2050 (IEA, 2021).

The current situation poses a real problem requiring an international and coordinated effort. However, the necessary conditions and regulations must be in place to drive progress and encourage the investment needed to deliver the desired net zero by the 2050 target.

Case study: Hybrid solution for standard European refinery
Fuels used in the transport sector account for 24% of total CO2 emissions, including aviation at 2% (13.9% of total transportation emissions) (see Figure 2).

The emissions are produced in two phases: the fuel production phase and the combustion phase, when the fuel is used to power road and marine engines and airplane turbines.

Emissions during the production phase can be effectively reduced by a combination of operational improvements in the refineries and changes in feedstocks. However, a smart approach is needed, as the recommended solutions require modifications in the refinery configurations and big investments.

The suggested solutions presented can be defined as a hybrid configuration for a fuels production centre prepared for the transition towards net zero objectives. The configuration defines a feasible fuels production scheme with a consequential reduction in CO2 emissions.

Present situation
The present situation, or base case, considers a standard European refinery with a 100,000 barrels per day (BBL) processing capacity, with high conversion and bottom-of-the-barrel configuration, as well as state-of-the-art energy efficiency and emissions control systems (see Table 1)
Combination of grey refinery units with green and blue alternative units

The optional case, or suggested configuration, is based on the incorporation of carbon capture, green hydrogen generation, and synthetic fuels production units. The new configuration is optimised for a feasible scheme, where the operation of the refinery is reliable, the carbon footprint is reduced significantly, and the return on investment is attractive for the stakeholders.

These topics are described in more detail:
Carbon capture Carbon capture is focused on the units with the largest CO2 emissions in the refinery, the hydrogen production units (HPU) by the steam methane reforming process (SMR), which are real ‘CO2 factories’ that generate 9 kilograms of CO2 for each kg of hydrogen produced.

The SMR units are suitable for post-combustion carbon capture by means of the amine absorption process with high efficiency, so this technology is considered as a basis for the analysis.

The captured (or ‘sequestrated’) CO2 is subsequently used inside the refinery as feedstock for the production of synthetic fuels.

The amount of CO2 generated in the HPU is:
HPU unit capacity                           95,625 TPA
CO2 generated (CO2 HPU):            900,000 TPA

All the CO2 of the HPU will be considered as sequestrated.